Damped fishing rod

ABSTRACT

A fishing rod is provided in which unwanted vibration is damped and casting characteristics are improved. Vibration damping elastomeric material is provided as a tapered element within the hollowed rod blank near the rod tip and/or as an intervening layer between the rod blank and the rod grip.

BACKGROUND OF THE INVENTION

The present invention relates in general to fishing rods, and moreparticularly, to fly fishing rods made from fiber reinforced resin.

Fishing rods have been made from tapered hollow tubes for many, manyyears. The tapered hollow tubes are called blanks. Most modern fishingrods are made from blanks of fiber reinforced synthetic resin. Theblanks taper from a butt end having a larger diameter to a tip endhaving a smaller diameter. Reel seats, grips, line guides, and tips aremounted on the rod blanks to make a finished fishing rod. Fishing rodsand, especially fly fishing rods, are often provided in sections so therod may be transported in a case less lengthy than the assembled rod.

A typical fly fishing rod includes a grip and a mechanism for mounting areel near the butt end. A series of line guides are attached to the rodalong its length ending at the tip end. Line is fed from the reelthrough the line guides to the tip. In fly fishing particularly, theflexing characteristics of the rod are very important. The flexingcharacteristics have a major influence on the ability of a fisherman tocast a fly toward a desired location with a desired presentation uponthe water. To improve this flexing characteristic, rod builders haveused a wide variety of materials and designs. Bamboo has given way tovarious synthetic reinforced resins to achieve desirable flexcharacteristics. The taper and weight of the tube forming the rod blankhas also been carefully controlled. As rods in their finished states areoften sectional, the design of the joint holding the sections togetherhas been carefully thought out to provide appropriate flexingcharacteristics. Considerable efforts have been expended in designingand building fly rods to achieve flexing characteristics and thusimprove casting. However, the perfect fly rod has yet to be achieved.

SUMMARY OF THE INVENTION

Applicants have found that damping of the vibration characteristics of afishing rod over a portion of its length improves its castingcharacteristics. Such damping can be achieved by the insertion of adamping material into the fly rod over a selected portion of its length.The damping material is selected to attenuate and damp vibrations in therod thereby improving control over the line and the transfer of energyto the line and fly. Thus, in accordance with the invention, a fishingrod is provided having a damping material incorporated into the rod overa portion of its length.

Still further in accordance with the invention, a fishing rod isprovided having a damping material incorporated into the rod over aportion of the length near the tip end only.

Further in accordance with the invention, a fishing rod comprising atapered, hollow, tubular member is provided with a damping elementhaving a gently tapered conical shape adapted to be received snuglywithin the hollow rod.

Still further in accordance with the invention, a fishing rod isprovided with a tapered damping element having a taper identical to theinside taper of the rod near its tip.

Still further in accordance with the invention, a fishing rod having ahollow tapered body portion is provided with a damping element having ataper to match the inside taper of the body portion near its tip endwith the damping element being adhesively bound to the inside surface ofthe body portion over substantially the entire length of the dampingmember.

Further in accordance with the invention, a fishing rod is providedhaving a damping element between the rod blank and the rod grip.

Yet further in accordance with the invention, a fishing rod is providedin which a layer of damping material is positioned around the rod blankand encased by a thin hard cylinder within the grip providing a dampingaction between the rod and the grip.

It is the principal object of the present invention to provide a fishingrod having improved casting characteristics.

It is another object of the present invention to provide a fishing rodwhich provides improved casting control.

It is still another object of the present invention to provide a fishingrod having good flex characteristics and at the same time vibrationdamping characteristics allowing the fisherman to achieve longer andmore accurate casts.

It is another object of the present invention to provide a fishing rodwhich efficiently transfers energy to the fishing line.

It is still another object of the present invention to provide a methodof manufacturing an improved fishing rod providing improved dampingcharacteristics without interfering with other characteristics of therod or only minimally changing other characteristics in order to enhancethe rod's performance.

These and other objects of the present invention will become evidentfrom the following detailed description taken in conjunction with theaccompanying drawings which form a part hereof.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows schematically a fly fishing rod;

FIG. 2 shows a portion of the fly fishing rod of FIG. 1 enlarged andpartially cut away to reveal a damping element used in the presentinvention;

FIG. 3 shows a further enlarged portion of the fly fishing rod of FIGS.1 and 2 showing the damping element in greater detail;

FIG. 4 shows an enlargement of the grip portion of the fly fishing rodof FIG. 1 partially cut away to reveal a second damping element inaccordance with the present invention;

FIG. 5 shows the first mode of vibration of a conventional fly fishingrod;

FIG. 6 shows the second mode of vibration of a conventional fly fishingrod;

FIG. 7 shows the third mode of vibration of a conventional fly fishingrod; and

FIG. 8 shows the fourth mode of vibration of a conventional fly fishingrod.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings wherein the showings are made for thepurposes of illustrating a preferred embodiment of the invention onlyand not for the purposes of limiting same, FIG. 1 shows a fly fishingrod 10 having a tip 12 and a butt 14. The fishing rod 10 is built upon arod blank 16 which tapers from a larger diameter at the butt 14 to asmall diameter at the tip 12. The blank 16 is hollow and is fabricatedfrom a reinforcing fiber embedded in a resin. Such rod blanks areavailable from a number of sources in a wide variety of sizes andactions. Moreover, these rod blanks are available in fitted segmentsallowing one to disassemble a rod of about 8 to 10 feet into a moremanageable portions for transportation.

The fishing rod 10 is also provided with a number of guides 18 along itslength and a tip guide 20. A grip 22 is positioned on the rod near thebutt end 14. Reel mounting hardware and a reel 24 are also positionednear the butt end 14. A quantity of fly line 26 is contained upon thereel 24 and fed from the reel through the guides 18 and the tip guide20. All of the above-described elements are conventional and areavailable as finished assembled fly rods or as individual components forbuilding a fly rod.

The action characteristics of a fly rod describe the flexibility, linehandling, and power transfer characteristics of a particular fly rod.Fly rods are made in a wide variety of force carrying capacities andactions. The action of a fly rod has always been somewhat subjectivelydescribed as the final test of the action is how it feels in the handsof a fisherman and how it casts the fly line and a fly in real worldfishing situations. While not all characteristics of the action of agiven rod are fully understood, several factors are known to contributeto how a rod behaves. The stiffness and elasticity of the reinforcingfibers and resin used in creating the rod blank directly impact the feelof the rod. How the rod is tapered over its length affects the feel ofthe rod. The amount of reinforcing fibers and resin used in the rodaffects the feel of the rod. The distribution of weight over the lengthof the rod affects the feel of the rod. Other characteristics which areless easily quantified or described also affect the feel of a rod. Rodbuilding is still an art and many of the operations in rod building arestill carried out by hand by experienced craftsmen.

Applicants have found that the vibrational characteristics of a roddirectly and significantly affect its action. Moreover, applicants havefound that these vibrational characteristics and the damping thereof canbe computer modeled to a usable degree of accuracy. Further, applicantshave found that damping materials can be employed to reduce vibration atselected modes of vibration of the rod thereby improving the actioncharacteristics of the rod significantly.

Elastic bodies, such as fishing rods, have natural frequencies ofvibrations. The frequencies and manner in which things vibrate arecalled the modes of vibration. When elastic bodies are struck or givenenergy in some way, they often respond by vibrating in their naturalfrequencies or modes. Thus, the bowing of a violin results in vibrationof the violin strings in natural modes providing music. In a fishingrod, energy is put into the rod by the action of the fisherman movingthe rod back and forth to perform a cast. The desired result is thetransfer of the energy to the fishing line in a controlled manner so thefisherman may place the fly upon the water as he desires. Another affectof the introduction of this energy into the rod is the creation ofvibration in the rod. This vibration can divert energy from the fishingline, where it is desired, and can also interfere with control of theline.

A particular fly fishing rod was modeled numerically and the naturalmodes vibration of this rod were derived by applicants. The first modeof vibration in which the rod vibrates at approximately 2.65 hertz isillustrated in FIG. 5. In the first mode, the butt end is not displacedappreciably while the tip end is displaced most. The non-displacedlocation is called a vibrational node and the maximum displacementlocation is called an antinode. In the first mode, there is one mode andone antinode. A second mode of vibration in which the rod vibrates atapproximately 8.93 hertz is shown in FIG. 6. In the second mode, thereare two nodes and two antinodes producing a different distribution ofdisplacement along the rod. A third mode of vibration in which the rodvibrates at 17.86 hertz is shown in FIG. 7 and a fourth mode ofvibration in which the rod vibrates at 32.73 hertz is shown in FIG. 8.In the third mode, there are three nodes and three antinodes and in thefourth mode, there are four nodes and four antinodes. In the figuresnodes are marked with an "N" and antinodes are marked with an "A". Thesemodes of vibrations are the natural modes of vibrations associated withthis particular rod. In the figures, the location of motion in the modesof vibration is shown by the numbers across the lower scale. Zero on thefar left of each figure is the butt 14 end of the rod. One on the farright of each figure is the tip 12 end of the rod. As can be seen fromthe figures, the vibration does not really affect the butt end which isheld in the fisherman's hand but can result in considerable movement andjitter at the tip end of the rod. The tip end of the rod controls theline as it leaves the rod. The movement of the tip end of the rod has avery important affect on a cast and upon the feel of a rod in casting.When energy is put into the rod, all of the modes of vibration will beoccurring at once.

It is expected that other fly rods will vibrate in the four modesdescribed above. The frequencies of these modes will change due to rodweight, length, stiffness, and other factors. The expected frequencyranges are approximately:

First Mode--2-6 hertz

Second Mode--7-12 hertz

Third Mode--15-25 hertz

Fourth Mode--28-38 hertz

The frequencies described for the four modes of vibration illustrated inFIGS. 5-8 are low enough so that significant movement of the tip end ofthe rod occurs in each mode. The rod has time to move the tip over anappreciable distance with respect to the line. Applicants have foundthat removing or minimizing this vibration, especially at the tip end,greatly improves the casting characteristics and feel of a fly fishingrod.

Referring to FIG. 2, a portion of the rod 10 adjacent to tip 12 isshown. A portion of the rod length 16 is cut away to show constructionof the invention. The rod blank 16 is hollow and tapered. The extremetip 12 is very small in diameter and the internal hollow is often lessthan 1/8th of an inch in diameter. From the tip 12, the internal hollowbecomes gradually larger toward the butt end. Rod blanks are often madeby wrapping material about a steel mandrel and the size and taper of thehollow is very precisely known.

A short distance away from the tip 12 of the rod 10 seen in FIG. 2, thenear half of the rod blank 16 is shown cut away. A short portion ofempty hollow 32 is seen in this cut away portion. The hollow 32 is emptyall the way to the tip 12. A damping element 34 is also seen in FIG. 2.The damping element completely fills the hollow 32 for a portion of itslength extending from the tip end of the damping element 36 to the buttend of the damping element 38. Applicants have found that adequatedamping is achieved by providing a damping element near the tip end ofthe rod having a length of approximately 27 inches (68.6 cm.). Thedamping element 34 need not be positioned right at the tip of the rodbut can be spaced from the tip of the rod up to approximately 9 incheswhile still achieving adequate damping.

The length of the damping element 36 stated above will vary from rodmodel to rod model. A two handed salmon rod having an overall length ofabout 15 feet will perform but with a longer damping element 36, e.g.forty inches long. A six foot, one ounce, one weight rod will need adamping element of much less length, e.g. twelve inches long. Thepositioning of the damping element will also vary from particular roddesign to particular rod design. The damping element may be spaced fromabout 1 inch to 20 inches from the rod tip 12.

The damping element 34 and its relationship to the rod blank 16 is shownin greater detail in FIG. 3. The rod blank 16 is shown cut away in crosssection. The rod blank 16 tapers slightly toward the tip 12. Containedwith the rod blank 16 is the damping element 34. The damping element isfixed in position with respect to the rod blank 16 by a layer ofadhesive 42. The rod blank 16 and the damping element 34 will thereforemove in unison in all vibrational modes.

Weight is important in the behavior of a fly fishing rod. Moreover,because the tip of the rod moves furthest in casting and the rod flexesmore toward the tip than toward the butt, weight near the tip is mostimportant. Thus applicants have found improved casting and flexcharacteristics are achieved by the rod blank 16 being empty near thetip 12. Moreover, applicants believe that by dispersing microbubbles 44in the damping element 34, the weight of the damping element can beminimized while maintained adequate vibration damping characteristics.Microbubbles are not used in the present preferred embodiment but may behelpful in some rods.

The damping element 34 is not just an elastomeric body. Rather, it is abody fabricated from an elastomeric material selected to deadenvibrations of the frequency modes described above. An appropriateelastomeric material is available from Globe Rubber Works, 254 BeechStreet, Rockland, Mass. 02370. It is identified as Cast ElastomerCompound G4324-00 which is a diamine/isocyanate/synthetic urethaneprepolymer having a shore hardness of 93A, a tensile strength of 6,000psi, an elongation of 450%, a Young's Modulus of 16,000 psi, a Die CTear Strength of 370 pli, a Split Tear Strength of 100 pli and a reboundof 48%. Similar materials are available from others. Damping materialshave long been available because vibration is a problem in many areas.Particularly sophisticated materials have been developed for use onsubmarines and are available from defense contractors. Damping materialcan be obtained in a liquid-like consistency, mixed with microbubbles,cast into the appropriate shape, and cured. Once cured, the finisheddamping element 34 will have a taper and external dimensions closelymatching the internal dimensions of the hollow 32 in the rod blank 16.It has been found that the damping element 34 can be coated with anappropriate adhesive 42 and pushed into the rod blank 16. No specialpulling tool or the like is required. The damping element 34 is simplypushed in with a rod of appropriate size and the adhesive is allowed toset. The damping element 34 is then fixed to the rod blank 16 over itsentire length and performs its vibration damping function.

The damping element 34 is made by casting polyurethane material in asilicone mold. The silicone mold allows molding and removal of finishedparts without use of a mold release. The damping material is fitted intothe mold in the liquid state and cured at a temperature of about 250° F.for less than ten minutes. The finished damping elements are removedfrom the mold ready for coating with a liquid adhesive and insertioninto a rod blank.

Use of the above-described damping element 34 has been found to reducemost modes of vibrations significantly. In tests run on actual dampedand undamped identical rods, most of the damping modes illustrated inFIGS. 5-8 are significantly reduced. This is accomplished while addingonly minimal weight to the rod and minimal loading of the tip. Moreimportantly, blind tests were conducted by allowing experienced flyfishermen and women to compare otherwise identical damped and undampedrods. The damped rod was preferred. The test participants stated theycould cast further and more accurately. Fly line loop control wasimproved. Performance improvement on windy days was noticeable. As windcan induce vibration in a fly rod, this finding confirmed that thedamping treatment was a significant improvement.

A second means of decreasing and/or eliminating unwanted vibrations in afly rod is illustrated in FIG. 4. FIG. 4 shows, schematically, theportion of fly rod 10 as seen in FIG. 1 near the butt 14. A reel seat 52is mounted over the butt of the rod blank 16 closing the end of the rodblank. A pair of reel bands 54, 56 are mounted on the reel seat 52. Oneof the reel bands 54, 56 is conventionally mounted on threads or thelike (not shown) allowing the bands 54, 56 to be moved relative to oneanother. The bands 54, 56 are used to mount a reel 24 (FIG. 1) on thereel seat. This reel mounting mechanism is conventional.

Just forward of the reel seat 52 is the grip 62. With respect to flyrods, grips are conventionally constructed from cork and come in avariety of shapes to accommodate the preferences of fishermen. In normaluse, a fisherman will handle the fly rod 10 during casting by means ofthe grip 62 only. Thus, the only portion of the fly rod in contact witha relatively fixed structure is the grip 62 being held in the hand ofthe fisherman.

The grip 62 surrounds the rod blank 16. A first layer of adhesive 64 isapplied to a damping element 66 which is then applied to the rod blank.A second layer of adhesive 68 binds the damping element 66 to a rigidgrip liner 72 which is in turn bonded to the grip 62 by a third layer ofadhesive 74. The layers seen in FIG. 4 are shown in an exaggeratedthickness for purposes of clarity.

The grip liner 72 and the third layer of adhesive 74 prevent the grip 62from being compressed into the damping element 66 and, more importantly,isolates the grip 62 from the damping element 66. For some rod designs,the grip liner 72 and the third layer adhesive 74 may not be necessarybecause the grip 62 may have sufficient rigidity to perform thisfunction unassisted. The grip is also isolated from the reel seat sosupport of the rod is through the grip only.

The rod blank 16 will behave as a somewhat isolated body with respect tovibrations when the rod 10 is used in casting. The grip structure justdescribed acts to damp vibration in the rod 10 and the rod blank 16 asit is a damping member at the only point in which the rod blank 16 issupported by a relatively fixed structure, the angler's hand.

Applicants have found that the relatively small mass of damping materialpositioned as described between grip 62 and rod blank 66 significantlydamps the modes of vibration described above. The layer 66 does not needto be very thick. Applicants currently prefer a layer of about 0.06inches (1.5 millimeter). Moreover, because the damping material ispositioned under the grip, the mass of the damping material does notsignificantly affect the felt characteristics of the rod. The mass is atthe position of the grip as far from the tip as is possible. The tip canbe kept light.

Because the damping layer 66 is relatively small in volume andpositioned under the grip, microbubbles 44 (seen in FIG. 3) are notneeded in the layer 66. Rather, a simple uniform layer of dampingmaterial can be used. Microbubbles may be used for weight reduction.

While not readily apparent from FIG. 4, the rod blank 16 has a gradualtaper to it even near the butt end. Because of this, it is advantageousto have a gradual taper to all of the layers between the rod length 16and the grip 62. This provides uniform layer thickness over the lengthof the handle. This can be accomplished by casting or otherwise formingthe damping element 66 and the rigid grip liner 72 to have enlargedinterior diameters but otherwise identical tapers to the rod blank 16near the butt end. Alternatively, the damping element 66 can be cut fromsheet material in a trapezoidal form and simply wrapped around the rodblank 16 and adhesively bound to the rod blank with a fine seam at thepoint where the trapezoidal sides meet one another.

Alternatively, a rigid grid liner 72 of uniform cross section can beused. A hollow conical damping element 66 fills the volume between therod blank 16 and the rigid grid liner 72. The damping element 66 can becast in place or, preferably, cast in fixture and glued in place aftercuring.

The damping element 66 is fabricated from an elastomeric materialselected for appropriate damping characteristics with respect to themodes of vibrations expected. Applicants have found appropriate dampingmaterials to be available from Globe Rubber Works (previouslyidentified) in a liquid form for casting into hollow conical members orinto flat sheet form for cutting and adhesive binding to the rod blank16.

The above-described damping elements 44, 66 can be used as illustratedin conjunction with one another or separately. The damping advantages,while working together, also work independently. One can use either thedamping under the grip, 66 the damping within the rod blank near thetip, 34 or both. At present, use of element 44 in the tip alone ispreferred. The damping element 44 may be divided into two pieces for usein two sections of multiple section rods.

Another method of providing damping material near the tip 12 of thefishing rod is the coating of the inside surface of the hollow 32 of therod blank with a layer of curable elastomeric damping material and thenallowing the layer to cure. A damping material is selected withappropriate damping characteristics, viscosity, and cure rate. Thematerial is introduced by injection into the rod blank. A coating isformed of appropriate thickness and cures in place. the thickness of thecoating can be controlled by selecting an appropriate viscosity for thematerial. Alternatively, the rod blank can be completely filled over aportion of its length. The position of the damping element is controlledby insertion of a dam or block into the blank before introduction of theliquid damping material. Because the rod blank is tapered, a dam ofselected site can be pushed into the rod blank to a selected positionand will be held in place. Thus, this "cast- in-place" method can beused to position a damping element of selected length at virtually anyposition in the rod.

The invention has been described with respect to preferred embodiments.Modifications and alterations will occur to others upon the reading andunderstanding of this specification. It is our intention to include allsuch modifications and alterations insofar as they come within the scopeof the appended claims or the equivalents thereof.

Having thus described the invention, it is claimed:
 1. An improvedfishing rod comprising:an elongated tapered, hollow resilient tubehaving a butt end of a first diameter and a tip end of a second diametersmaller than said first diameter, said tube having a stiffness; and, atapered elastomeric vibration damping element having a substantiallength when compared to the length of said fishing rod sized to fitsnugly within said hollow resilient tube over substantially the entirelength of said damping element disposed within said hollow resilienttube spaced from said rod tip and adhesively fixed to said tube, saiddamping element substantially fills the interior of said rod, saiddamping element having a stiffniess substantially less than saidstiffnless of said tube and adapted to damp vibrations of said tube,said tapered damping element being in contact with the inner surface ofsaid fishing rod over the length of said damping element, and saiddamping element is of a uniform material over its entire extent.
 2. Animprovement in a fishing rod having an elongated resilient tube having astiffness, a tip end and a butt end, a reel seat and a cork grip, theimprovement comprising:a vibration damping element having asubstantially uniform thickness fabricated from an elastomeric materialhaving a stiffness substantially less than said stiffniess of said tubesaid damping element surrounding said tube and positioned between saidtube and said grip and adapted to damp vibrations of said tube.
 3. Animproved fishing rod comprising an elongated tapered resilient hollowshaft having a butt end; a tip end; a stiffness; a handle and a reelseat; the improvement comprising, damping means in said shaft adapted toattenuate vibration of said shaft, said damping means comprising anelastomeric body of uniform material having a substantial length whencompared to the length of said fishing rod substantially filling theinterior of said shaft, said elastomeric body fitting snugly within saidhollow shaft over substantially the entire length of said elastomericbody, in contact with the inner surface of said hollow shaft over thelength of said elastomeric body and adhesively fixed to said shaft overat least a portion of the length of said shaft spaced from said shafttip end, said elastomeric body having a stiffness substantially lessthan the stiffiess of said shaft.
 4. An improved fishing rod comprisingan elongated tapered hollow resilient tube having a butt end of a firstdiameter and a tip end of a second diameter smaller than said firstdiameter said tube having a stiffness;a reel seat; a grip; a taperedvibration damping elastomeric element disposed within and adhesivelyfixed to said hollow resilient tube spaced from said tube tip having astiffness substantially less than said stiffness of said tube adapted todamp vibrations of said tube; and, a body of vibration dampingelastomeric material between said resilient tube and said grip having astiffness substantially less than said stiffness of said tube adapted todamp vibrations of said tube.
 5. An improved fishing rod comprising anelongated tapered, hollow, resilient tube having a butt end of a firstdiameter and a tip end of a second diameter smaller than said firstdiameter, said tube having a Young's modulus; and,a tapered elastomericvibration damping element of uniform material having a substantiallength when compared to the length of said fishing rod disposed withinand substantially filling said hollow resilient tube, said dampingelement having a Young's modulus substantially lower than said Young'smodulus of said tube sized to fit snugly within said tube, adhesivelyfixed to said tube over the entire length of said damping element andadapted to damp vibrations of said tube.
 6. An improved fishing rodcomprising an elongated tapered, hollow resilient tube having a butt endof a first diameter and a tip end of a second diameter smaller than saidfirst diameter, said tube having a Young's modulus; and,a taperedelastomeric vibration damping element having a substantial length whencompared to the length of said fishing rod adapted to damp vibration ofsaid tube, said damping element disposed within and being in contactwith the inner surface of said hollow resilient tube over the length ofthe damping element and adhering to said hollow resilient tube, saiddamping element fitting snugly within said tube over substantially theentire length of said damping element, said damping element having anelongation of about 450%, a Young's modulus substantially lower thansaid Young's modulus of said tube, said damping element Young's modulusbeing about 16,000 pounds per square inch; and said damping elementbeing spaced from said tube tip end.
 7. An improvement in a fishing rodhaving an elongated resilient tube having a stiffness, a tip end and, abutt end, a reel seat, a cork grip, the improvement comprising:avibration damping element having a substantially uniform thicknessfabricated from an elastomeric material having a stiffness substantiallyless than said, stiffness of said tube said damping element surroundingsaid tube and positioned between said tube and said grip and adapted todamp vibrations of said tube; and, a rigid grip liner surrounding saiddamping element, said rigid grip liner being surrounded by said grip. 8.An improvement in a fishing rod having an elongated resilient tubehaving a stiffness, a tip end and a butt end, a reel seat and a corkgrip, the improvement comprising:a vibration damping element fabricatedfrom an elastomeric material having a stiffness substantilly less thansaid stiffness of said tube said damping element surrounding said tubeand positioned between said tube and said grip and adapted to dampvibrations of said tube; a rigid grip liner having a substantiallyuniform diameter over its length surrounding said damping element, saidrigid grip being surrounded by said grip, and, said damping elementfilling the volume between said rigid grip liner and said resilienttube.
 9. The improvement of claim 7 wherein said elastomeric layer issurrounded by a rigid tube which is in turn surrounded by said grip.